Thermostatic adjusting mechanism for scales



Nov. l', 1927. 1,647,378

w. F. s'rlMPsoN E1' Ar.` Y

THERMOSTATIC ADJUSTING MECHNISM FOR SCALES I Filed June s, 1925 x uuenlom,

Patented Nov. 1, 1927.

mais? vUNITI-:li STAT-Es ie'isxrlrri*f oi-Fica f j WALTER F. s'rIMrsoNAND WILLIS E. FINoI-I, or LOUISVILLE, IIravfrIICKY;` sari) vIINCII` AssIGNoa'ro `sii-II)A sTIMPsoN; v

I THERMOSTATIC ADaUsTINe MEcHANIsI/I ron. scALEs.

j Application mea June s, 1925. serial No. 35,765.

. 4Our invention relatesto thermostatic devices used in lconnection.l with weighing scales for the purpose fof compensating for variations due to temperature changes. It 5 is an object/of the invention to obtain a construction which will full compensate for all .temperature changes within a large range of variations, further to obtain a construction which, `when once set, requires no further attention, furtherto obtain a simpleV construction whichxis easily manufactured and installedinconnection with weighing `mechanism. y l

lVith these Vobjects in view, the invention consists. in the construction as hereinafter set forth. 1 Inj thedrawings:- f n Figure 1 is a plan view of a scale lever showing my improved thermostat applied thereto. Y

Figure f2 isyfyaj-longitudinal section therethrough.

Figure 3 is a cross-section showing the construction of thermostat. v

A is a scale lever of any suitable construction, but which, as shown, is designed as the main platform supporting lever of a weighing scale. B, B are the knife-edge fulcrum bearing pins and C, C are the knifeedge pivots for supporting the platform,

not shown. j

D is the long arm of the lever which is channel shaped in cross-section and is provided at its outer end with the parallel bearplates is arranged a carriage G having rollers H and H forming an anti-friction engagement with the bearing plates. At the outer end of the carriage is the pivot pin I for' engaging with the steelyard rod or other connected scale member, not shown.

Vith the construction as thus described,

the roller carriage is capable of comparaing plates E and Ff Between these bearingu perature, such for instance as 100o Fahr.,l Y and wev have found that a considerable movement of the pivot is required Vfor full compensation. To secure this required movement, we havedevised a novel construction of thermostat, as follows;

J is a compensating metallic bar bent intoa spiral form so as to obtain al considerable lengthv within small space limits.. A plurality of such4 coils.' are ,arranged in parallelism Vand are mounted on'a common shaft K, preferably by providing each coil with a hub portion L Awhich maybe sleevedon said` shaft. andsecured. thereto by a set screw M. As specifically'shown, we have employed foursuch coils arranged in pairs and their outer ends [connected by yoke members N. The yokes N are provided with projecting ears O which are cross-connected by a shaft or pin P and centrally ofthese pinsis connected the linkrod.A Q which extends through the channel arm D and is connected with the carriage G. The arrangement is such that the several coils co-act in adjusting the rod Q so as to avoid overloading any one coilvand also to secure greater accuracy by averaging the movement of the severalvcoils to minimize individual variations thereof. Furthermore, by this arrangement, each Vcoil may be restricted in width, thereby avoiding any tendency to buckle laterally due to temperature l(hanges as might be the case with a wider With the construction as described, to set the thermostat, the lever is placed in any suitable jig, not shown, for relatively locating the fulcrum pivots B and steelyard pivot I at some predetermined temperature, such as degrees Fahr. The rod Q which is connected to the carriage G is then attachedV to the pin P and the shaft K on which the several coils of the thermostat are sleeved is mounted in recessed bearings R and R on the cross bar A of the lever A. As shown this bar A is of angle cross section and the shaft K and coils J are concealed within the angle thereof. The shaft K is secured by screws K after which set screws S engaging threaded apertures in the hubs L Vmay be tightened to hold said hubs anguabout an adjustment of the rod Q, and pivot I to compensate for elongation or contraction inthe lever.

vWhat wedesiretoclaim is: c

1. In a scale, a .thermostat for compensating for temperature variations comprising a plurality of spirally coiled thermostatic bars, an equalizer connection between the outer end of said bars, a member to be actuated by said` thermostat through said equalizer connection, and means for individually anchoring the inner ends of said thermostatic bars.

2. In a scale, a thermostat for compensating for temperaturevariations, comprising aV plurality of spirally coiled thermostatic bars,'a yoke connection vbetween the outer ends of adjacent coils, an equalizer connection between a pair of yokes, a bearing actuated by said equalizer connection,- and means for individually anchoring the inner ends of said coils. f Y

3. In a scale, athermostat for compensating the temperature variations, comprising a plurality of spirally coiled thermostaticbars, a hub connected to the inner end of each coil, a shaft on which 'said hubs are sleeved, set screws for adjustably securingl said hubs to said shaft, an equalizer connection between the outer ends of said coils and a bearing adjusted by said equalizer connection.

4. .In a scale, the combination with a lever' having spaced iXed and movableV bearings, oi a thermostat for adjusting said movable bearings, Comprising al plurality of spirally coiled thermostatic bars, a shaft on which said coils are mounted, spaced bearings on said lever for receiving said shaft with the coils therebetween, means for anchoring said shaft and the inner ends of the coils thereon, an equalizer connection between the outer ends'of said coils and a connection between said equalizerfconnection and said movable bearing. Y

`5. In a scale, a thermostat-for compensating forl temperature variations comprising a plurality of comparatively narrow spirally coiled thermostatic bars a connection through which said bars may operate in unison and means'tor individually anchoring said bars.

V6.V In a scale,` a thermostat for compensating for temperaturevariations comprising a plurality of comparatively narrow spirally coiled .thermostatic bars parallelly arranged, a member to be actuated operated conjointly by said bars and means for individually anchoring said bars. K

In testimony whereof we aiix our vsignatures. f i

WALTER F; sTIMPsoN. WILLIS E. FINcH. 

